Public Health benefits by implementing digital symptom diaries for COVID patients from Cologne

Background

High rate of people infected with SARS-CoV-2 and their contacts in Cologne, Germany required innovative tools for notification, monitoring and reporting. The digital tool for COVID19 (DiKoMa) provides self-service symptom diaries allowing (a) the stratification for prioritized telephone contact by the health authority and (b) training a machine learning (ML) model that predicts infections with prevailing dominant variant (PDV) from early symptom profiles (SP).

Methods

Pseudononymized SP covering the first week of diary recordings were included for training (16646 index, 11582 contacts). A balanced random forest (BRF) model was trained to differentiate early predictive symptom patterns of different PDV and contact persons. Model evaluation was performed using sex and age stratified cross validation (CV), the model was validated on SP recorded from days 1 and 6.

Results

From 03/20 to 02/22, 90478 indeces and 75444 contact persons reported symptoms and health status, covering 46% and 42% of all reported cases, respectively. Diaries contained between 1-52 entries (566791, median 2). Daily analysis of entries, prioritized according to age, prevalent co-morbidities and detoriation of symptoms allowed risk adjusted follow up even during phases with high case notification rates. The top 5 predictive factors of the BRF were immunization, cough, dysgeusia and dysnosmia, fatigue, and sniffles to differentiate infection between wildtype, three PDV and contact persons (CV AUC 80.6%, Validation AUC 77.1%).

Conclusions

The use of digital symptom diary surveillance helps to provide appropriate medical support for patients on a large scale. Machine learning shows potential for symptom based risk assessment to differentiate PDV for future outbreaks and can thus become a valuable tool alongside specific laboratory diagnostics.

Key messages

• Digital symptom diaries are a powerful and widely accepted tool to attend COVID19 patients in isolation. They allow risk stratification for follow up and are a low-threshold service.

• Machine learning supports index case identification by symptom analysis and can thus become a valuable tool alongside specific laboratory diagnostics.

Overcoming resistance in a BRAF V600E-mutant adenocarcinoma of the lung

We report on a patient with an adenocarcinoma of the lung harbouring a BRAF V600E mutation who benefited from combination therapy with dabrafenib-trametinib after developing resistance to vemurafenib. To our knowledge, our report shows, for the first time, that combination therapy with dabrafenib-trametinib can overcome vemurafenib resistance in a BRAF V600E-mutated adenocarcinoma of the lung.

Magnetization dynamics of Landau structures: tuning the response of mesoscopic magnetic objects using defects

Magnetic vortex cores are interacting with and can even be annihilated by artificial defects, such as holes. These defects have been fabricated by focused ion beam milling (FIB) into the magnetic domains, domain walls and the center of square-shaped vortices, known as Landau structures. We report the imaging of the magnetization dynamics of Landau structures containing holes by means of x-ray magnetic circular dichroism photo-emission electron microscopy (XMCD-PEEM). Due to the high lateral and temporal resolution of this method, the magnetic excitation spectrum, which is characteristic for the vortex-hole interaction, is investigated in detail. We find that the vortex core as well as domain walls can be trapped by small holes. With the help of micromagnetic simulations we show that the vortex gyrotropic motion frequency is enhanced, whereas the amplitude is significantly reduced in the case of non-centric holes in domain walls.

Tumor endothelial interaction, CD44+/CD24- stem cell signature, and prognosis in early-stage breast cancer

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Background: The effects of tumor-endothelial interaction on global gene expression in breast cancer are not yet well characterized. We hypothesized that gene expression signatures induced by tumor-endothelial interaction might be of clinical relevance. Methods: To this aim we set up an ex vivo co-culture model with human benign and a panel of 6 malignant breast epithelial cells in combination with human venous and microvascular endothelial cells and determined associated gene expression changes with cDNA microarrays. Pretreatment gene expression profiles of 295 early stage breast cancers from the Netherlands Cancer Institute with a median follow up of 12.6 years allowed evaluating in vitro effects in vivo. Results: The most prominent response to co-culture was the induction of a set of “M-phase cell cycle” genes in a subset of breast cancer co-cultures, which were absent in co-cultures with normal breast epithelial cells. While in monoculture tumor cells containing the stem cell like CD44+/CD24- signature showed a lower expression of the “M-phase cell cycle” genes than the CD44-/CD24+ cells, in the co-cultures with CD44+/CD24- cells these genes were induced. Interestingly, these tumor cells co- expressed a set of angiogenic factors such as VEGF, PTN, and FGF12 mRNA at significantly higher levels. In vivo, the expression of the gene set derived from the co-culture was remarkably coherent providing a basis for segregation of tumors into two groups. In a univariate analysis, early stage tumors with high expression levels (n= 137) of “M-phase cell cycle” genes had a significantly lower distant metastasis-free survival (p=1.8e-5) (50 % at 10 years) and overall survival rate (p= 5e-9) (52 % at 10 years) than tumors with low expression levels (n= 158) (metastasis-free survival: 73 %; overall survival: 84 % at 10 years). Conclusions: Our results suggest that the interaction of tumor cells expressing the CD44+/CD24- stem cell like signature, implicating a low proliferative potential, with endothelial cells might explain the unexpected and paradoxical association of the CD44+/CD24- signature with highly proliferative tumors with an unfavorable prognosis. Multiple co-expressed angiogenic factors represent potentially interesting additional therapeutic targets.

No significant financial relationships to disclose.

A phase I study of tumor treating fields (TTFields) in combination with pemetrexed for pretreated advanced non-small cell lung cancer

e18500

Background: TTFields (tumor treating fields) are low intensity, intermediate frequency, alternating electric fields which slow the growth of solid tumors in-vivo, and have shown promise in pilot clinical trials in patients with advanced solid tumors. TTFields are a regional treatment which acts both by interfering with microtubules polymerization and by physical disruption of the cell structure during cytokinesis. It has been shown previously that TTFields sensitize non-small cell lung cultures to Pemetrexed. In-Vivo, TTFields did not increase pemetrexed related toxicity. Methods: A prospective trial was performed in 14, pretreated, stage IIIb-IV, NSCLC patients. Patients with brain metastases were excluded, as were patients with abnormal marrow, kidney, liver or cardiac functions. Patients with history of clinically significant arrhythmias or those having pacemakers were excluded as well. Patients received Pemetrexed 500mg/m2 IV q3w together with daily TTFields (12 h/day) using a portable medical device (NovoTTF-100L). The device generated 2 direction (AP and Lat), 150 kHz TTFields. Patients were followed every three weeks and had a lung CT every 9 weeks. The primary endpoint was the safety and tolerability of the NovoTTF-100L device in combination with pemetrexed. Results: The 14 patients received an average of 4 courses of pemetrexed (Range 1–9) and a cumulative TTFields treatment time of 182 weeks. The device was well tolerated as indicated in the device log files which showed an average daily use of 11±1 hours. There were no device-related, nor pemetrexed-related SAEs. In addition, no unexpected abnormalities were evident in the lab tests or EKGs, done every 3 weeks for all patients. There were no reports of arrhythmias. The only device related AE seen in all patients was dermatitis under the electrodes. This improved with meticulous skin care, topical steroid use and in extreme cases oral steroids. One patient (7.6%) had a CR, 1 a PR (7.6%), 9 SD (69.2%) and 3 PD (23%). 77% of patients were progression free at 12 weeks and the 6 month survival was 89%. Conclusions: TTFields are well tolerated when given together with pemetrexed. The excellent safety profile and initial efficacy results reported here justify further clinical testing.

[Table: see text]

[New therapeutic opportunities in metastatic renal cell carcinoma]

Until recently metastatic renal cell carcinoma was considered refractory to the available therapies. A better understanding of the molecular biology and the introduction of targeted agents led to a significant improvement in the prognosis of patients with metastatic renal cell carcinoma. In this paper the molecular pathology, specifically the deregulation of the oxygen adaption mechanisms leading to tumorangiognesis will be presented. Based on these fundamental mechanisms the targeted agents will be introduced. These agents have been tested in randomized phase III trials in different clinical and prognostic situations. The results and the side-effects of sunitinib, sorafenib, temsirolimus, everolimus and bevacizumab treatment will be presented leading to a possible treatment algorithm.

Dynamic vortex-antivortex interaction in a single cross-tie wall

A fascinating property of micromagnetism comes from the possibility to control the domain and vortex configuration through the sample shape and size. For instance, in a rectangular platelet a configuration containing a stable combination of vortices and an antivortex can be created. Such a single cross-tie wall can be understood as being a coupled micromagnetic system with three static solitons. Here we report on its magnetization dynamics including the vortex-antivortex interactions. The spectrum of eigenmodes is investigated as well as the effect of different vortex core orientations. We show that the vortex dynamics can be used to identify the core configuration, which is not directly accessible to x-ray microscopy because of its limited spatial resolution.

Effects of tumor stroma interaction on global gene expression in breast cancer

10006

Background: Perturbations in cell-cell interaction are a key feature of cancer. However, the systematic effects of cell-cell interaction on global gene expression in cancer are largely unexplored. We hypothesized that gene expression signatures induced by cell-cell interaction might be of clinical relevance. Methods: We simulated tumor-stroma interaction in vitro by systematically co-cultivating each of 7 different breast cancer cell lines with stromal fibroblasts from 3 different sites, and determined associated gene expression changes with cDNA microarrays. A dataset of pretreatment gene expression profiles from 295 early stage breast cancers (stage 1 and 2) with a median follow up of 12.6 years allowed us to evaluate the prognostic significance of the gene expression signatures of specific cell-cell interactions derived from our ex vivo models. Results: The most prominent response to epithelial-mesenchymal interaction was an induction of interferon-response genes (IRG), observed in 4 of the 7 breast cancer cell lines in co-culture with fibroblasts, but not in normal mammary epithelial cells. In response to close contact with these breast cancer cells, the fibroblasts secreted type I interferons, which, in turn, induced expression of the IRG in the tumor cells. Immunohistochemical analysis of human breast cancer tissues showed that Stat1, the key transcriptional activator of the IRG, and itself an IRG, was expressed in a subset of the cancers, with a striking pattern of elevated expression in the cancer cells in contact with, or close proximity to, the tumor stroma - paralleling the response seen in our ex vivo model. In vivo, expression of the IRGs was remarkably coherent, providing a basis for segregation of the 295 early-stage breast cancers into two groups by unsupervised hierarchical clustering with the IRG. Tumors with high expression levels (n=161) of IRG were associated with significantly shorter overall survival; 59% at 10 years versus 80% at 10 years for tumors with low expression levels (n=134) (log-rank p=0.001). Conclusions: Our results suggest that an interaction between some breast cancer cells and stromal fibroblasts can induce an interferon response, and that this response may be associated with a greater propensity for tumor progression.

No significant financial relationships to disclose.

Time resolved magnetization dynamics of ultrathin Fe(001) films: spin-pumping and two-magnon scattering

The time-resolved magnetic response of ultrathin epitaxial Fe(001) films grown on GaAs(001) and covered by Au, Pd, and Cr capping layers was investigated by time and spatially resolved Kerr effect measurements. The magnetization was excited by an in-plane magnetic field pulse using the transient internal field generated at a Schottky barrier while the wavelength of the excitation (resonant mode) was roughly 4 microm. Each of the three cap layers affected the spin relaxation in a unique way. Au cap layers resulted in the bulk Gilbert damping of the Fe film. Pd cap layers caused an additional Gilbert damping due to spin-pump or spin-sink effects. Cr cap layers lead to a strong extrinsic damping which can be described by two-magnon scattering. In this case the strength of the extrinsic damping can be controlled by a field induced shift of the spin wave manifold with respect to the excited k vector.

Micromagnetic dissipation, dispersion, and mode conversion in thin permalloy platelets

Micron-sized ferromagnetic Permalloy disks exhibiting an in-plane ferromagnetic vortex structure are excited by a fast rise time perpendicular magnetic field pulse and their modal structure is analyzed. We find azimuthal and axial modes. By a Fourier filtering technique we can separate and analyze the time dependence of individual modes. Analysis of the experimental data demonstrates that the azimuthal modes damp more quickly than the axial modes. We interpret these results as mode conversion from low-frequency azimuthal modes to the fundamental mode which is higher in frequency, i.e., mode-mode coupling in a system with a single Landau-Lifshitz-Gilbert phenomenological damping constant alpha.

Cutaneous plasmablastic lymphoma in an HIV-positive male: an unrecognized cutaneous manifestation

Plasmablastic lymphoma (PBL) is a rare and relatively new entity originally described in HIV-infected individuals. This subset of Epstein-Barr-virus (EBV)-related non-Hodgkin lymphomas is now regarded as a distinct clinicopathological category of AIDS-associated lymphomas occurring preferentially in the oral cavity and showing a poor prognosis. We describe for the first time an EBV-associated PBL with an isolated cutaneous distribution on the lower extremities in an HIV-infected heterosexual male and point to the unique clinical, morphological and immunophenotypic characteristics of this lymphoma. The patient presented with fast growing solid and livid nodules on both legs. The large, blastic tumor cells showed the following immunophenotype: CD138+, CD45+, CD20-, CD10-, CD3-, CD30-, bcl-2-, bcl-6-, LMP-1- and EMA-. The proliferation fraction (Mib-1) was >90%. EBV association was demonstrated by in situ hybridization (EBV-encoded RNAs 1/2). Polymerase-chain-reaction-based DNA analysis demonstrated a clonal IgH rearrangement in the absence of a bcl-2/IgH translocation. PBL in HIV patients may occur not only in the oral cavity, but can probably involve any other organs including the skin.

Fourier transform imaging of spin vortex eigenmodes

Thin-circular lithographically defined magnetic elements with a spin vortex configuration are excited with a short perpendicular magnetic field pulse. We report the first images of excited magnetic eigenmodes up to third order, obtained by means of a phase sensitive Fourier transform imaging technique. Both axially symmetric and symmetry breaking azimuthal eigenmodes are observed. We observe strong oscillations of the magnetization in the central part of the magnetic elements. The experimental data are in good agreement with micromagnetic simulations.

[Primary intraocular lymphoma with unusual clinical presentation and poor outcome]

BACKGROUND

Primary intraocular lymphoma is a distinct subset of primary non-Hodgkin's lymphoma of the CNS. In general, the primary non-Hodgkin's lymphoma of the CNS is rare, accounting for 1 % of all non-Hodgkin's lymphomas and less than 1 % of all intraocular tumors.

HISTORY AND SIGNS

A 70-year-old man was hospitalized in June 2002 because of acute loss of vision on his left eye. A severe vitreous hemorrhage was observed. Ultrasound showed solid subretinal lesions at the posterior fundus. Diagnostic vitreous surgery including a biopsy was performed. An intraocular malignant B-cell lymphoma was determined by immunohistochemistry. General screening revealed no further manifestations of the lymphoma.

THERAPY AND OUTCOME

The patient initially refused any therapy until a painful secondary neovascular glaucoma with complete loss of visual function developed, thus prompting us to perform an enucleation. The following immunohistochemical examination confirmed the initial diagnosis. A chemotherapy with high-dose methotrexate and leucovorin rescue was initiated.

CONCLUSIONS

Primary intraocular lymphoma can present as diffuse uveitis refractory to corticosteroids. Diagnosis can be difficult and is often delayed.

[Supraclavicular isolated lymphadenopathy]

Anhand einer Fallbeschreibung wird auf die Differentialdiagnose der Lymphadenopathie eingegangen. Ein 19-jähriger Patient präsentiert sich mit lokalisierter Lymphknotenschwellung. Er klagt über einen Reizhusten seit sechs Wochen, Nachtschweiss besteht schon seit zwei Jahren. Die Lymphknoten sind schmerzlos, derbe und nicht überwärmt oder gerötet. Klinisch und labormässig keine Hinweise auf eine Infektion, weshalb eine Feinnadelpunktion durchgeführt wird. Mittels Zytologie und verschiedenen Zusatzuntersuchungen wird die Diagnose eines Hodgkin Lymphoms Stadium II gestellt.

[A 63-old patient with right-sided hypogastric pain at 6 months after appendectomy]

Anhand einer Fallbeschreibung werden die Differentialdiagnosen bei rechtsseitigem Unterbauchschmerz mit den entsprechenden weiterführenden Abklärungen besprochen. Schwerpunktmässig wird im Kommentar anhand des beschriebenen Falles auf die Bildgebung von Dünndarmprozessen und im speziellen auf das diffuse, grosszellige B-Zell-Lymphom (Schwerpunkt Therapie, Prognose) eingegangen.

Ultrafast generation of magnetic fields in a Schottky diode

For the development of future magnetic data storage technologies, the ultrafast generation of local magnetic fields is essential. Subnanosecond excitation of the magnetic state has so far been achieved by launching current pulses into micro-coils and micro-striplines and by using high-energy electron beams. Local injection of a spin-polarized current through an all-metal junction has been proposed as an efficient method of switching magnetic elements, and experiments seem to confirm this. Spin injection has also been observed in hybrid ferromagnetic-semiconductor structures. Here we introduce a different scheme for the ultrafast generation of local magnetic fields in such a hybrid structure. The basis of our approach is to optically pump a Schottky diode with a focused, approximately 150-fs laser pulse. The laser pulse generates a current across the semiconductor-metal junction, which in turn gives rise to an in-plane magnetic field. This scheme combines the localization of current injection techniques with the speed of current generation at a Schottky barrier. Specific advantages include the ability to rapidly create local fields along any in-plane direction anywhere on the sample, the ability to scan the field over many magnetic elements and the ability to tune the magnitude of the field with the diode bias voltage.

Imaging precessional motion of the magnetization vector

We report on imaging of three-dimensional precessional orbits of the magnetization vector in a magnetic field by means of a time-resolved vectorial Kerr experiment that measures all three components of the magnetization vector with picosecond resolution. Images of the precessional mode taken with submicrometer spatial resolution reveal that the dynamical excitation in this time regime roughly mirrors the symmetry of the underlying equilibrium spin configuration and that its propagation has a non-wavelike character. These results should form the basis for realistic models of the magnetization dynamics in a largely unexplored but technologically increasingly relevant time scale.

[Iodine-induced hyperthyroidism (iodine-induced Basedow's disease): a current disease picture]

Iodine-induced thyrotoxicosis or "jodbasedow phenomenon" has been reported throughout the world since iodine has been administered to treat endemic goitre. Nowadays, iodinated radiocontrast agents and the antiarrhythmic drug amiodarone are the most common sources of excess iodine load subsequently leading to iodine-induced thyrotoxicosis, especially in elderly patients with underlying goitre. The aim of the study was to identify the number of cases of iodine-induced thyrotoxicosis among patients with thyrotoxicosis in a large urban hospital. Over an 18-month period thyrotoxicosis has been diagnosed in a total of 39 patients. Eight patients with iodine-induced thyrotoxicosis (5 female, 3 male; mean age 60.6 years) have been identified (20%). In all patients with iodine-induced thyrotoxicosis, iodine exposure with a mean iodine dose of 21.5 g was documented 2 to 16 weeks before diagnosis (iodinated radiocontrast agents in 5 patients, amiodarone in 2 patients, kelp tablets in 1 patient). Clinical features were predominantly tachyarrhythmias and heart failure, while 6 of 8 patients had goitre (thyroid volume 31 to 193 ml). Thyroid antibodies were not detected. Diagnosis was confirmed in 5 of 8 patients with increased urinary iodine concentrations (3436 to > 6000 nmol/24 h), and in 3 of 8 patients with a low tracer uptake in thyroid scintigraphy (1 to 4%). Treatment consisted of methimazole in all patients, additional tional beta-blockers and lithium in 4 patients, and prednisone in 5 patients. The mean treatment ment duration was 9.2 months, and patients became euthyroid after a mean treatment duration of 6.4 weeks. One patient (with still elevated free thyroxine levels) died of myocardial infarction 4 weeks after antithyroid drug therapy had been installed. The incidence, mechanisms and features of iodine-induced thyrotoxicosis are discussed. Iodine-induced thyrotoxicosis is a common disease, and the recognition and treatment of iodine-induced thyrotoxicosis, particularly in elderly patients and patients with goitre, are of clinical importance.

Search for oncogenic regulators in an autocrine tumor model using differential display PCR: identification of novel candidate genes including the calcium channel mtrp6

A hemopoietic multistep tumor model, in which IL-3 dependent PB-3c mast cells, following expression of v-H-ras progress in vivo to IL-3 producing autocrine tumors has previously been established. Central for this oncogenic progression is a recessive step, which is reversible by cell fusion and leads to stabilization of IL-3 mRNA with concomitant activation of the autocrine loop. Comparing the IL-3 dependent PB-3c and the IL-3 autocrine V2D1 tumor cells with differential display PCR revealed 12 differentially expressed genes of which eight were upregulated and four downregulated in the tumor. They included four proteases (mouse mast cell protease 2, granzyme B, pepsinogen F and serine protease 1) and two metabolic enzymes (adenine phosphoribosyltransferase and fructose1,6-bisphosphatase). For validation, expression of the identified genes was tested in independent PB-3c precursor clones and their tumor derivatives. Expression of an endogenous retroviral IAP element and three unknown transcripts were consistently upregulated in all tumor lines. In somatic cell hybrids, two of these unknown cDNAs showed a dominant and one a recessive expression pattern. One transcript, expressed in the precursor but downregulated in the tumor cells, was cloned and identified as the murine calcium channel mtrp6.

Direct identification of differentially expressed genes by cycle sequencing and cycle labelling using the differential display PCR primers

Differential display PCR (DD-PCR) is an mRNA fingerprinting technique to identify differentially expressed genes by comparative display of arbitrarily amplified cDNA subsets. This attractively simple screening method was, however, followed by a labour intensive multistep identification procedure for DD-PCR products. In this report we demonstrate for the mouse mast cell protease 2 (MMCP-2) and the cytotoxic T-lymphocyte associated gene transcript CTLA-1 a streamlined approach by (i) direct cycle sequencing with the upstream differential display (DD) primer, followed by (ii) the PCR based generation of an antisense northern probe with the downstream anchor primer.